1. Field of Invention
The present invention relates generally to an apparatus for supplying air to an enclosed space and in particular to an apparatus using a nozzle to supply air to an enclosed space. Still more particularly, the present invention relates to an air supply apparatus that supplies air through a nozzle at different rates in different locations within a cabin in an aircraft.
2. Background Description
Cabin air systems for aircraft are designed to provide a safe and comfortable cabin environment at different altitudes. At high altitudes, the passenger cabin is pressurized to enable occupants to breathe normally. Further, the cabin air systems are also designed to provide cooling for equipment that may be located within the passenger cabin.
The passenger cabins for specialized aircraft typically have large concentrated heat loads due to electronic equipment located within the passenger cabin. The size and location of the heat load is often different between aircraft of the same type because of configuration changes over time and varying customer requirements. If the cooling air within the passenger cabin is not properly distributed, a failure of electronic components may occur. Additionally, occupant discomfort and distraction due to overheating hot and cold spots also may occur.
Aircraft with high heat loads require customized cabin air systems to distribute air in a manner that provides sufficient cooling to heat loads and does not result in hot and cold spots in the passenger cabins. Currently, when an aircraft is being designed for a specialized use, an identification of locations for heat generating equipment and occupants are specified. With this specification of heat loads and occupants, an air distribution system is custom designed for that particular aircraft. Nozzles for an air distribution duct running along the length of the passenger cabin are designed to provide the appropriate airflow to maintain a uniform temperature within different locations of the passenger cabin.
This type of solution works well unless a reconfiguration of the aircraft occurs after the aircraft has been constructed. With such a change, the cabin air system may no longer provide uniform temperatures within the passenger cabin because of changes in the location or size of heat loads within the passenger cabin. If the system is unable to maintain a uniform temperature within the passenger cabin, a new set of nozzles must be designed to replace the original nozzle system. These types of changes are expensive and time consuming.
Different control zones may be used to meet temperature uniformity. This type of system, however, is often uneconomical because of the number of control zones that would be needed to maintain temperature uniformity.
Another currently used solution provides a separate cooling system for the heat loads. This type of solution, however, results in an underutilized air distribution system. Further, additional weight and energy use occurs when using a separate cooling system for these heat loads. Therefore, it would be advantageous to have an improved cabin air supply system.